| 1 | //===-- Linux implementation of sigaltstack -------------------------------===// |
|---|
| 2 | // |
|---|
| 3 | // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
|---|
| 4 | // See https://llvm.org/LICENSE.txt for license information. |
|---|
| 5 | // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
|---|
| 6 | // |
|---|
| 7 | //===----------------------------------------------------------------------===// |
|---|
| 8 | |
|---|
| 9 | #include "src/signal/sigaltstack.h" |
|---|
| 10 | #include "hdr/types/stack_t.h" |
|---|
| 11 | #include "src/__support/libc_errno.h" |
|---|
| 12 | #include "src/__support/macros/config.h" |
|---|
| 13 | #include "src/signal/linux/signal_utils.h" |
|---|
| 14 | |
|---|
| 15 | #include "src/__support/common.h" |
|---|
| 16 | |
|---|
| 17 | #include <sys/syscall.h> |
|---|
| 18 | |
|---|
| 19 | namespace LIBC_NAMESPACE_DECL { |
|---|
| 20 | |
|---|
| 21 | LLVM_LIBC_FUNCTION(int, sigaltstack, |
|---|
| 22 | (const stack_t *__restrict ss, stack_t *__restrict oss)) { |
|---|
| 23 | if (ss != nullptr) { |
|---|
| 24 | unsigned not_ss_disable = ~unsigned(SS_DISABLE); |
|---|
| 25 | if ((unsigned(ss->ss_flags) & not_ss_disable) != 0) { |
|---|
| 26 | // Flags cannot have anything other than SS_DISABLE set. |
|---|
| 27 | // We do the type-casting to unsigned because the |ss_flags| |
|---|
| 28 | // field of stack_t is of type "int". |
|---|
| 29 | libc_errno = EINVAL; |
|---|
| 30 | return -1; |
|---|
| 31 | } |
|---|
| 32 | if (ss->ss_size < MINSIGSTKSZ) { |
|---|
| 33 | libc_errno = ENOMEM; |
|---|
| 34 | return -1; |
|---|
| 35 | } |
|---|
| 36 | } |
|---|
| 37 | |
|---|
| 38 | int ret = LIBC_NAMESPACE::syscall_impl<int>(SYS_sigaltstack, ss, oss); |
|---|
| 39 | if (ret < 0) { |
|---|
| 40 | libc_errno = -ret; |
|---|
| 41 | return -1; |
|---|
| 42 | } |
|---|
| 43 | return 0; |
|---|
| 44 | } |
|---|
| 45 | |
|---|
| 46 | } // namespace LIBC_NAMESPACE_DECL |
|---|
| 47 | |
|---|
